Toxicity induced by nanoparticles

Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics.     

Evaluation of larvicidal activity of the aerial extracts of a medicinal plant,Ammannia baccifera (Linn) against two important species of mosquitoes,Aedes aegypti and Culex quinquefasciatus

ObjectiveTo analyze the larvicidal effect of the aerial extracts of Ammannia baccifera on two important mosquito species, Aedes aegypti and Culex quinquefasciatus.MethodsThe larval mortality of fourth instar larvae of A. aegypti and C. quinquefasciatus after 24h and 48h of treatment were observed separately in control 50, 100, 150, 200, 250, 300, 350, 400, 450 and 500 mg/L concentrations of the aerial extracts (methanol, ethyl acetate, chloroform) of A. baccifera.ResultsBased on the probit analysis, the 24h and 48h aerial methanol extract of A. baccifera LC₅₀value of C. quinquefasciatus was found to be in 164.00 mg/L and 107.00 mg/L and LC₉₀values for C. quinquefasciatus was found be in 310.00 and 261.00 mg/L. The 24h and 48h aerial part of methanol extract of A. baccifera LC₅₀value of A. aegypti was found be in 226.00 mg/L and 186.00 mg/L and LC₉₀values was found be in 476.00 and 309.00 mg/L.ConclusionsThe results indicate that the A. baccifera could be effectively used for the control of mosquito larvae and the possibility of exploiting for the development of commercial larvicides a plant widely occurring in India.     

INFLAMMATORY FIBROID POLYP OF PROXIMAL ILEUM CAUSING RECURRENT INTUSSUSCEPTION

SUMMARY A 64-year-old female presented with episodes of small bowel obstruction. Ultrasound and barium meal showed a polypoidal lesion in the proximal segment of small bowel. The patient underwent emergency surgery because of signs of impending acute intestinal obstruction. Pathology showed characteristic features of an inflammatory fibroid polyp (IFP) which is an important though rare benign cause of small bowel obstruction. We document clinical and pathological aspects of this case.     

STUDY OF GLOMERULAR FUNCTIONS IN NEONATES

Glomerular function of neonates (25 full term and equal number of preterm neonates) at birth, on day seven and day fourteen were estimated by endogenous Creatinine clearance (CCr). The Preterm were divided into three groups viz. Group I (Gestation age (GA) 30-32 weeks), Group II (GA 33-34 weeks) and Group III (GA 35-36 weeks). Group IV consisted of 25 term neonates. Serum creatinine (in mg/dl) in all the groups of preterm ranged from 0.92 ± 0.153 to 1.204 ± 0.154 and in term neonate from 0.562 ± 0.175 to 1.148 ± 0.247 showing that the levels were inversely proportional to the period of gestation. Besides the Serum Creatinine levels in all groups of Preterm as well as term neonates were found to fall significantly (p < 0.001) during the first and second week. Glomerular filtration rate (GFR) in Group I were 16.603 ± 2.519, 19.786 ± 2.078 and 23.720 ± 2320 on day one, seven and fourteen respectively showing progressive improvement during the first two weeks. The GFRs were also found to be directly proportional to the GA. In addition the levels of GFR were found increasing significantly during the second week compared to that on day seven in all the groups of preterm neonates. GFR''s in Group I & II on all the three occasions were significantly lower (p < 0.001) than those of term counterparts, however the GFR on the first day in Group III neonates was lower than group IV, the difference was insignificant (p > 0.05). The increase in GFR in Group I on the three occasions was linear but insignificant (p > 0.05). The rise was more rapid & significant (p < 0.001) during the second week in Groups II & III. On the contrary the rate of improvement of GFR in full terms was quite rapid during the first week and gradual over the second week of life.KEY WORDS: GFR preterm & term neonates, Serum creatinine     

Bone impregnated hip screw in femoral neck fracture: Clinicoradiological results

Background:

Femoral neck fractures are treated either by internal fixation or arthroplasty. Usually, cannulated cancellous screws are used for osteosynthesis of fracture neck of femur. The bone impregnated hip screw (BIHS) is an alternative implant, where osteosyntehsis is required in femoral neck fracture.

Materials and Methods:

The BIHS is a hollow screw with thread diameter 8.3 mm, shank diameter 6.5 mm and wall thickness 2.2 mm and holes in the shaft of the screw with diameter 2 mm, placed in a staggered fashion. Biomechanical and animal experimental studies were done. Clinical study was done in two phases: Phase 1 in a group of volunteers, only with BIHS was used in a pilot study and phase 2 comparative study was done in a group with AO cannulated screws and the other group treated with BIHS.

Results:

In the phase 1 study, out of 15 patients, only one patient had delayed union. In phase 2, there were 78 patients, 44 patients in BIHS showed early union, compared to the rest 34 cases of AO cannulated screws Out of 44 patients with BIHS, 41 patients had an excellent outcome, 2 had nonunions and one implant breakage was noted.

Conclusions:

Bone impregnated hip screw has shown to provide early solid union since it incorporates the biomechanical principles and also increases the osteogenic potential and hence, found superior to conventional cannulated cancellous screw.